1. Technical Field
This disclosure relates generally to radio-frequency (RF) circuits, and, more specifically, to RF power detection.
2. Description of the Related Art
RF circuits typically perform a variety of operations to process a received signal. Such operations may include filtering the signal, demodulating it, sampling it, etc. In order to perform some of these operations, various circuits in the receiver chain may require that the RF signal have a signal strength within a particular range (e.g., a range of 60-80 dB). Often, however, an RF signal is too weak by the time it arrives at the receiver. To account for this, the receiver may attempt to amplify the signal before processing it further.
In many instances, RF circuits employ a feedback loop in which an incoming signal passes through an amplifier and then a power detector, which measures its power. If the signal strength is too high or too low, the RF circuit adjusts the gain of amplifier accordingly. This form of feedback loop is commonly referred to as an automatic gain control (AGC) system.